Have a look on ebay for Avid bleeds kits. You will see quite a few at a cost between £25 and £35. If you look at the bottom of the screen you should see kits available from Hong Kong. These kits include all the bits you need apart from the Dot5.1 fluid. You can buy the fluid from Halfords – don't buy the BikeHut stuff though (125ml bottle. The regular Halfords Dot5.1 is the same price for 250ml!
For instructions on how to bleed the brakes just search on YouTube for Avid Brake Bleed Process – there is an instructional video. The process is very easy and makes a huge difference to the brakes. I did my Elixir R's a few weeks ago (they had been spongey since I bought them and although good I had been a little disappointed) and they are now vastly improved.